PCK files (like other build products) should be deterministic based on their inputs. Removed calls to Math::rand() that are being used to generate padding.
Looks like these were introduced as part of adding encryption support, but the padding being random does not have any cryptographic significance. This can be trivially inferred since file blocks that happen to be aligned don't get padding anyway.
If there's a desire to indroduce something that functions as a nonce it should probably be added explicitly and only if encryption is enabled.
remove Math::rand() calls in editor_export_platform.cpp
follow up to make consistent with pck_packer
067807c1cb